Network penetration testing

A comprehensive network penetration test combines several activities. Not every engagement includes all of them — the scope is agreed up front — but a thorough assessment typically draws on:

• Network discovery and mapping — identifying the structure, perimeter, and third-party connections, and reviewing router, switch, and firewall configuration.
• Exploitation testing — attempting access first without credentials, then as a standard user, then as a privileged user, using what discovery revealed.
• Server and configuration audit — reviewing account policies, permissions, patch levels, audit logs, and known vulnerabilities on a sample of servers.
• DMZ review — auditing internet-facing servers and testing them from both the DMZ and internal perspectives.
• Firewall rule review — checking rules against business need, and flagging excessive access, conflicts, and weak configuration.
• IDS/IPS testing — confirming intrusion detection or prevention systems actually detect and defend, safely and repeatably.
• Wireless and workstation testing — assessing Wi-Fi security and what an unauthorised user at a desk could achieve.

External network testing starts from the internet with no access and measures your exposure to a stranger. Internal testing starts from inside — modelling a phished laptop, a rogue insider, or a compromised supplier — and measures how far a foothold could spread. Because a hard shell with a soft centre is such a common weakness, many organisations run both and treat them as complementary.

Expect a clear scope agreed in advance, testing carried out by qualified professionals, and results that are technically reviewed and quality-assured before delivery. A good report ranks findings by severity, explains the business risk, and gives concrete remediation steps — and a good firm will walk you through the results and offer a retest once you have addressed them, so you can prove the fixes worked.